What does this light mean?

[bigglew]

Today a light came on my dash board that read "Emiss Maint". What does this usually mean?

Thanx

[90xjDave]

Your O2 sensor would be the first thing I would check.

[2offroad]

Eject...Eject...Eject.

sorry long weekend

[Rev Den]

What year?? If it is a 90 the light means the timer has triggered the light......pull the timer.

REv

[bigglew]

It's an 89 with 80,000 miles on it.

thanx

[CheapXJ]

yup, it's a timer.

look for a semi-translucent box under the dash on the driver's side (it's in pretty plain view)

unplug it and be happy.

replace the O2 sensor if you've noticed a significant drop in highway mileage.

[bigglew]

what does the timer do and what sets it off?

[AZ Jeff]

The emissions timer gets a signal from the odometer. At the specified number of miles (I remember it being 82,500, but I may be a bit off), it turns on the light on the dash.

The purpose of this was to insure that when your typical XJ reached the 80K mark, the owner would be motivated to take it in for replacement of the Oxygen Sensor, which dies about that mileage.

The "official" way to get the light turned off is to use the Chryco diagnostic module that plugs into the ECU circuit. All it does is disable the timer so the light will go out.

My recommendation, unless you want to pay the dealer to defeat the lamp with the diagnostic tool, is to unplug the timer, and if you are at all concerned, put in a new O2 sensor.

[Rev Den]

Originally posted by bigglew
what does the timer do and what sets it off?

It counts time.....


What sets if off??? Time.

The emissions timer runs from date build everytime the motor runs. When it reaches a certain amount of time, it turns on the light. Actually my 90 had a recall to install the fuse for the timer, because the factory did not. I tossed the fuse in the glovebox and pitched the notice.


DG

[CheapXJ]

Originally posted by AZ Jeff
The emissions timer gets a signal from the odometer. At the specified number of miles (I remember it being 82,500, but I may be a bit off), it turns on the light on the dash.

The purpose of this was to insure that when your typical XJ reached the 80K mark, the owner would be motivated to take it in for replacement of the Oxygen Sensor, which dies about that mileage.

The "official" way to get the light turned off is to use the Chryco diagnostic module that plugs into the ECU circuit. All it does is disable the timer so the light will go out.

My recommendation, unless you want to pay the dealer to defeat the lamp with the diagnostic tool, is to unplug the timer, and if you are at all concerned, put in a new O2 sensor.

for an 87-90 XJ, it is a mechanical timer. there's no reset, no "disable" no ecu control. throw the old one away and install a new one (or just throw the old one away and forget about it)

[AZ Jeff]

Originally posted by CheapXJ
for an 87-90 XJ, it is a mechanical timer. there's no reset, no "disable" no ecu control. throw the old one away and install a new one (or just throw the old one away and forget about it)

I stand corrected here. My description ONLY applies to the post-Renix system with OBD-I.